I was just reading the topic below and got a little curious to know what my method of sparging would be (doh!). My method of sparging…

Equipment:
5 gallon igloo water cooler

Method:
1) Add additional water to cooler until it is full
2) Drain until wort is no longer visible in cooler
3) Continue to drain, add more water until cooler full
4) Repeat step three until I have enough wort for boil

So basically I am fly sparging I think, I just don’t have a continuous flow. I want to increase my efficiency (currently 60-65%), so here are my questions.

1) Is there a way I can batch sparge in a 5 gallon igloo cooler?
a. If so, how?
2) If I can’t batch sparge
a. At what rate should I be draining?
b. Does it matter how I am adding the additional water?
c. What temp should the additional water be?
d. What else can I do to increase my efficiency?

Batch sparging in a 5 gal cooler may be ok for small beers. But you may not have the room in your lauter tun to add enough water to effectively batch sparge for larger beers, hence your low efficiency.

With batch sparging you are putting all the sugar into solution and draining, whereas with fly sparging you are slowing rinsing the grain bed (continually). You should make sure you are getting conversion by performing an iodine test.

If you are using BTP the scedule lets you know the volume in vessel if you entered your mash tun. Take a look below, you can see the amount in vessel, and collected amounts in my batch sparge. I'm using a 10 gal rubbermaid/igloo with ss false bottom.

Thanks for the reply. I have been researching some more as well and think I am batch sparging. However, I am not completely drianing the tun and then refilling, stirring, and draining. Do you think I will gain efficiency by adding that to my process?

First, 'jawbox' is correct that you will need more than a 5 gallon tun if you are ever going to make large beers ... and I will add that 5-gallons is also insufficent for a 'partigyle' which is a nifty way to increase the efficiency of your brewing day (sure, it's more work to brew two batches in one day, especially if you have only one kettle, but the setup and cleanup are the same, whether one batch or two). I therefore recommend at least a 10 gallon round beverage cooler or 48 quart rectangular ice chest.

Coincidentally, I posted the following message on rec.crafts.brewing yesterday under the subject "Flood Sparging" (WAS: Vorlauf Question), and I've also included a response that I received:

On Dec 29, 2:02 pm, Bill Velek <billve...@alltel.net> wrote:

>> Denny and Don, I'd like to discuss this a little bit more, if you don't>> mind. I first learned the term "flood sparging" a few years ago in some>> Australian brewing forums, and, IIRC, I think maybe Graham Sanders (also>> an Australian) discussed it during one of his podcasts. As I explained,>> my understanding is that the difference between 'fly' and 'flood' is>> that 'fly' involves a continuous sprinkling of sparge water whereas>> 'flood' apparently means to drain the tun completely, and then adding>> more sparge water -- but without stirring as is done with 'batch'>> sparging. As I said, that sounds like what you are doing, Don.

snip

>> Now, the reason I'd like to discuss this further is because I have a>> _THEORY_, which I mentioned in a previous post (I believe it was in this>> r.c.b. forum), but received no comment. My 'theory' is that the sugar>> water contained within the grain particles has a higher gravity than the>> surrounding water (that is certain), and that perhaps this causes a>> pressure difference which induces an osmotic process to occur toward>> equilibrium, causing the sugars to be leached out of the grain particles>> rather than merely washed off the surface. If this is true, then it

nope. osmosis requires a semi-permeable membrane and you don't have one here, and even if you had one, osmosis would force the water inside the area surrounded by the membrane and not the sugar outside (unless you construct a membrane that is permeable for sugar and not for water).

what you are dealing with is mostly a _distribution_ process. this is something the - for example - is taught in physical or analytical chemistry classes.

you can see the grains as pieces of cloth or sponge containing a sugary solution. now when adding the sparge water you mix the "pure" water with the sugary water in the gains and you distribute the sugar more or less evenly in the whole environment, the stirring of course speeds this up. how much sugar is retained, depends on the total volume of liquid that still remains within the gains relative to the volume of sparge water added.

lets assume for the sake of argument that the contained volume is 1/4 of the volume of the sparge water added per batch. then the concentration of sugar after adding the sparge water would 1/5 of the orginal percentage. after a second (batch) sparge it would would be thus 1/25 and so on.

now if you'd reduce the amount of water added, the efficiency of the process is increased per total amount of water used at the cost of having to do more sparges. e.g. if you'd use half the amount of water you had have 1/3 the original sugar left after the first iteration, but only 1/9 (compared to 1/5) for the same amount of water.

reducing the amount of water to the limit of drops would give you the fly sparging process. this would allow to extract the maximum amount of sugar with the minimum amount of water, or more sugars with the same amount of water.

however, without the advantage of being able to speed up the distribution process by stirring. you can imagine each water addition to be a thin layer of water slowly sinking though the grain bed and stirring it would destroy the concentration gradient. this also explains the importance of having a slow runoff with fly sparging and why it doesn't matter for batch sparging.

what you call a 'flood'-sparge would simply be a less efficient version of the 'batch' sparge. depending on how fast you add the water there would still be some "stirring", but not as much. one can hypothesize why somebody would want to do this, but i don't think it is worth it.

>> would explain how both 'batch' and 'flood' sparging work, at least in>> part. And if that is the case, then stirring is probably not really>> necessary, although it might speed up the process somewhat. If this is>> true, then soaking time would naturally become an important factor,>> i.e., is it better to wait 2 minutes, 5 minutes, 10 minutes, etc. I

if you had really significant diffusion processes, those would take _much_ _onger, more of the order of days. so this would be rather pointless.

>> think I'll try letting it sit for 5 minutes or so, which won't take any>> more time than I now spend for stirring and vorlauf.

if you are so much interested in increasing efficiency, you'd have to do one more batch sparge, but how much gain this would get you, depends on the distribution of volumes (see above). if it were 1/10, which seems much more realistic to me (i used the numbers above for easy math), then you'd have less than 1 percent of the sugars left after two water additions.

of course, the model i'm giving is rather simplified, but i am certain it is pretty close to reality. the same model applies, for example, to the rinsing cycles of washing machines. "ecological" washing machines use much less water and more rinsing cycles.

hope that helps,axel.

>> I think I'll give that method a try during my next brew session and see>> what sort of results I get, but I also wanted to toss it out here for>> some consideration. It might be a solution to the occasional obertieg>> problem that I sometimes have. Any thoughts?>>>> Cheers.>>>> Bill Velek -- portal to my "HOMEBREWING" sites:www.tinyurl.com/29zr8r>> My other sites: www.velek.com~www.2plus2is4.com~www.grow-hops.com

Now, I didn't invent the name or the concept of 'flood sparging' (or 'batch sparging without stirring', if you prefer); I was just describing what some Australian brewers were apparently doing. I'll need to do some research to find out if they are still doing this or if they later learned that it was inefficient and abandoned the method. But if they are still doing it, I'd imagine it's because it works ... or works well enough considering that it makes sparging a little easier.

So, if 'axel' is correct, then my 'osmosis' theory was apparently wrong and stirring should be crucial to efficiency. By the way, 'Don' responded that he is making good beer without stirring, but he doesn't know what his efficiency is and doesn't have any records from his 'fly' sparging days for comparison anyway. Despite Axel's comments, I am still planning to try a 'flood' sparge during my next session, just to see for myself.

I haven't had time to digest Axel's calculations, so I can't comment on them.

I look forward to hearing any comments from my friends here.

EDIT: By the way, I meant to add a question that, while it might not technically be "osmosis", isn't there some mechanism at play here that might tend to force the sugars from within grain particles out into the lower gravity water? I find it hard to believe that all of the sugars from a sparge come entirely from the coating of sugar left on just the outside of the grain particles, but maybe that's why 'fly' sparging has greater efficiency than 'batch' sparging -- maybe the slow flow of sparge water is not just moving around the grain particles but instead is actually flowing through them.

So it sounds like I am sort of "Flood Sparging". My next brew (this weekend) I will perform a true batch sparge. I will stir before I drain the tun once and then refill the tun wait 10 minutes, stir and drain again. I will post back with my efficiency.

At what rate should I drain the tun both times? Fully open or partially?

When you batch sparge, you can drain as fast as your tun will let you without sticking.

I batch sparge in a 5 gallon cooler (it's 5.2 gallons right to the brim). If you get good efficiency, you can make up to about a 1.050 beer with a single sparge. Bigger beers require 2 sparges. Above about 1.065 OG, I need to make less than 5 gallons or add sugar or extract to hit my target.

It's definitely usable, and it's great for the smaller beers that I usually make, but it does get a bit cramped if you like to make a lot of big beers.

billvelek wrote:By the way, I meant to add a question that, while it might not technically be "osmosis", isn't there some mechanism at play here that might tend to force the sugars from within grain particles out into the lower gravity water? I find it hard to believe that all of the sugars from a sparge come entirely from the coating of sugar left on just the outside of the grain particles, but maybe that's why 'fly' sparging has greater efficiency than 'batch' sparging -- maybe the slow flow of sparge water is not just moving around the grain particles but instead is actually flowing through them.

You're thinking of diffusion (osmosis being the special case of diffusion through a semi-permeable membrane). I think the case you're describing is another special type of diffusion since the sugar wouldn't be freely exchanged with the surrounding liquor because of interactions with the grain particles.

I've often wondered if this was one of the reasons crush has such a big effect on efficiency in a quickly drained batch sparge. I imagine small particles mostly only need to be rinsed, whereas larger particles might require some time for the sugar to diffuse out. It might explain why some people seem to get an efficiency bump from waiting before draining the sparge and others don't.

In a similar vein, I recently tried a "punctuated sparge", wherein I drained the first runnings to the top of the grain bed. Then, I added the sparge water a quart at a time, allowing the liquor to drop close to the top of the grain bed before each addition. Finally, I fully drained the tun. I ended up getting 90% efficiency, which is in line with what I've been getting with a standard batch sparge these days.

Yes, diffusion is essentially what I meant when I said osmosis (I'm not a scientist and don't know the difference -- scientifically -- between a semi-permeable membrane and a large number of molecules still clumped together -- some still attached to or within the grain husk, and some not). I also made what I guess was the false assumption that just because there are a number of sugar molecules still stuck within that clump, and no sugar molecules outside the clump, that there would be a force of some sort to cause the diffusion; but now that I've thought about it a bit more, I'm not even sure that that is true because it would be no different than the stratification that we will sometimes see in a free liquid -- not only stratification of heat layers but also of gravity layers (think black and tan). I am now thinking that -- lacking any 'force' that would otherwise interplay to force diffusion to occur -- it would probably occur only as a result of a brewer forcing water or lower gravity wort through the particles, intentionally or not, by the flow of water through the grain bed during the sparge or by mixing.

Your 'punctuated' sparge sounds interesting, but if I understood you correctly, it didn't change your efficiency; however, are you saying that with the 'punctuated' sparge that you did NOT stir whereas I presume that with your usual 'batch' sparge that you DO stir?? In other words, did the 'punctuated' sparge replace stirring? ... and if so, you still reached the usual efficiency? That's interesting, but on the other hand It _sounds_ like your 'wait' time between each 'punctuation' was merely the time it took to drain a quart of wort, which wouldn't take long, so I also wonder if -- by adding just a quart at a time -- this is not really much closer to 'fly' sparging (which would actually be continuous) than it would be to 'batch' sparging.

Not a 'force' so much...
Ouch... this is getting to a scale smaller than my area of expertise, and Physical Chemistry was not the easiest semester of my life, so take my answers with some skepticism, but...

Osmosis is just sort of the reverse of what we're discussing. A semi-permeable membrane is essentially a barrier that allows water alone to pass. If you have more of something in solution on one side of such a structure, water will travel toward that side, diluting that concentration toward the concentration on the other side. The higher the concentration of a solute, the quicker the concentration will increase in the surrounding water. Stirring increases this rate by moving the solute away from the areas of high concentration, maximizing that concentration gradient.

Diffusion is movement of the compound in solution down a concentration gradient toward an area of lower concentration, primarily due to random molecular motion. In a grain particle, I expect there is movement of water in to form a more stable hydrogen bond dependent structure around the solute which may help to push sugar out of the particles. Meanwhile, there should be movement of sugar out of the particles and into the surrounding solution. That movement will be slowed somewhat by pore size of the particles and chemical interactions, probably hydrogen bonds, with the particles.

The unanswered question is how fast this occurs.

I suspect, however, that it might be more difficult to maintain a good black and tan with 150oF beer due to the higher rate of diffusion with higher temperature. Want to try the experiment?

The 'punctuated' sparge is a hybrid technique, discussed in BYO last year, that is designed to be as fast as batch sparging but which avoids oxidation of the grain bed by not fully exposing the grain to air. I did fully drain the tun at the end, however, to hit my volume. I drained slightly slower than normal; basically I set it to as fast as I could add the water. I usually stir well and didn't stir at all after the first vorlauf. I actually decided to give this a shot because I was running a little slow and I wasn't in the mood to risk stirring the grain and getting a stuck sparge.

I mention it only because it seems to be very similar to the Original Poster's method. I expected to take a big hit in efficiency and was very surprised to see no difference. For reference, I also made a no-sparge Bitter recently and got 75% efficiency. Years ago now, my first all-grain batch from my local shop's crush gave me 50%.

Yes, 'punctuated' sparge is basically what I was doing. The one thing I did not do was the vorlauf, which I think would contribute greatly to my efficiency. Also, in step 3 I was letting the wort below the grain bed and then refilling as apposed to refilling when the wort is just above the grain bed (small difference I feel).

Over the weekend I tried 'batch' sparging with better success. I ended up with ~70% efficiency (10% better). I did end up with two stuck sparges though! So I think my increase in efficiency could be attributed to two things. One, stirring the grain bed with every drain. Two, I added the wort back into the tun to free the first stuck sparge.

As far as process is concerned I like the 'punctuated' sparge more. I think my next brew I will try that method again, remembering to perform the vorlauf.

Also my stuck sparges may be contributed to the recipe, Oatmeal Stout. It called for a pound of Flaked Oats.

Yes, oats can increase the chance of a stuck sparge. A B-glucanase rest can reduce those chances a bit. Also, don't crush the oats.

If you got a higher efficiency from the batch sparge than your fly sparge, then the first place to look is your manifold design. That situation often indicates channeling or a design that leads to draining from a limited area.

Vorlauf probably won't increase your efficiency much, though it is a type of stirring, so it may help somewhat, but it can decrease the amount of husks in the boil which may lead to astringency.

It sounds like you wouldn't want to increase your crush much, if you're already getting stuck sparges, so you might look into minimizing the dead volume in your tun, if possible.